1. Technical Field
The present invention relates in general to data processing systems and in particular to use of a command line. Still more particularly, the present invention relates to a system, method and computer program product for providing command-line warnings on a data processing system.
2. Description of the Related Art
In computing, a command line interface or CLI is a method of interacting with a computer via a text terminal. Commands are entered as lines of text (that is, sequences of typed characters) from a keyboard, and output is also received as text. CLIs originated when teletype machines were connected to computers in the 1950s. In terms of immediate interaction and feedback, they represented an advance over the use of punch cards.
With the use of cathode ray tubes (CRTs) as interface devices, CLIs began evolving toward graphical user interfaces (GUIs) like Microsoft Windows®, Mac OS®, and the X Window System and were largely supplanted by GUIs when Microsoft Corporation, in response to the success of Apple's release of the Macintosh® OS in 1984, introduced Windows® the following year. Nevertheless, a significant minority of sophisticated computer users prefer to use CLIs, some due to visual disability, but most because they feel that CLIs provide an environment with enhanced productivity. They are most often used by programmers and system administrators, especially in Unix®-based operating systems; in engineering and scientific environments; and by a smaller subset of technically advanced home users.
In its simplest form, a CLI displays a prompt, the user types a command on the keyboard and terminates the command (usually with the Enter key), and the computer executes the command, providing textual output.
A program that implements such interface is often called a command line interpreter or shell. Examples include the various Unix® shells (sh, ksh, csh, tcsh, bash, etc.), the historical CP/M®, and DOS's command.com (“Command Prompt”), the latter two based heavily on Digital Equipment Corporation's RSX™ and RSTS™ CLIs. Microsoft's next operating system, Windows® Vista®, will include support for a new command line interface named MSH™ (Microsoft Shell, codename Monad), which hopes to combine features of traditional Unix® shells with their object oriented .NET® framework. Current Windows® CLI programs like DOS and Windows Script Host™ are commonly considered inadequate or insecure. MinGW is a third-party software for Windows that offers a true Unix® CLI.
Some applications provide both a CLI and a GUI. One example is the CAD program AutoCAD®. The engineering/scientific numerical computation package Matlab® provides no GUI for some calculations, but the CLI can handle any calculation. The three-dimensional-modeling program Rhinoceros 3D® (used to design the cases of most cell phones, as well as thousands of other industrial products) provides a CLI (whose language, by the way, is distinct from Rhino's scripting language). In some computing environments, such as the Oberon® or Smalltalk® user interface, most of the text which appears on the screen may be used for giving commands.
Certain commands, when invoked at a command line, can be destructive if improperly invoked. While many proposed solutions to command line entry problems have been proposed, none has proven adequate. These solutions have included flashing a series of ‘are you sure’ messages to a user and asking them to acknowledge the message before proceeding, the problem being that the messages are seldom any more captivating than any other message received from the command line. The user frequently presses ‘yes’ without reading the message in order to proceed. In addition, this prompting of messages works poorly when called from a script.
No solution to the problems of the prior art exists.